Which is nonpolar: #CF_4# or #CH_2F_2#?

1 Answer
Jun 6, 2016

Answer:

#CF_4# is non-polar.

Explanation:

Molecular polarity results from the vector sum of the individual #C^(delta+)rarrF^(delta-)# dipoles. Given a tetrahedron (and #CF_4# certainly assumes this structure), the #C-F# dipoles sum to #0# (remember that the vector sum is the geometric sum). The #C-H# bond is fairly non-polar, and thus their equivalent vector sum with #C-F# dipoles is non-zero.

The same situation obtains when non-polar #C(Cl)_4# is compared to polar chloroform, or (more polar) methylene chloride.